1 #ifndef __TIMER_H__
   2 #define __TIMER_H__
   3 
   4 #include <sys/time.h>
   5 
   6 //! A SIMPLE CLASS FOR TIME MEASUREMENTS.
   7 //
   8 class Timer
   9 {
  10   private:
  11 
  12     //! The timer value (initially zero)
  13     off_t _usecs;
  14 
  15     //! The timer value at the last mark set (initially zero)
  16     off_t _usecs_at_mark;
  17 
  18     //! Used by the gettimeofday command.
  19     struct timeval _tstart;
  20     
  21     //! Used by the gettimeofday command.
  22     struct timeval _tend;
  23     
  24     //! Used by the gettimeofday command.
  25     struct timezone _tz;
  26 
  27     //! Indicates whether a measurement is running.
  28     bool _running;
  29 
  30   public:
  31 
  32     //! The default constructor.
  33     Timer() { reset(); }
  34     
  35     //! Resets the timer value to zero and stops the measurement.
  36     void reset() { _usecs = _usecs_at_mark = 0; _running = false; }
  37 
  38     //! Mark the current point in time (to be considered by next usecs_since_mark)
  39     void mark() { stop(); _usecs_at_mark = _usecs; cont(); }
  40 
  41     //! Resets the timer value to zero and starts the measurement.
  42     inline void start()
  43     {
  44       _usecs = _usecs_at_mark = 0;
  45       gettimeofday(&_tstart, &_tz);
  46       _running = true;
  47     }
  48 
  49     //! Continues the measurement without resetting the timer value (no effect if running)
  50     inline void cont()
  51     { 
  52       if (_running == false)
  53       {
  54         gettimeofday(&_tstart, &_tz);
  55         _running = true;
  56       }
  57     }
  58     
  59     //! Stops the measurement (does *not* return the timer value anymore)
  60     inline void stop()
  61     {
  62       gettimeofday(&_tend, &_tz);
  63       if(_running){_usecs += (off_t)(1000000) * (off_t)(_tend.tv_sec - _tstart.tv_sec) + (off_t)(_tend.tv_usec - _tstart.tv_usec);}
  64       _running = false;
  65         //return _usecs;
  66     }
  67 
  68     //! Time at last stop (initially zero)
  69     off_t value() const { return _usecs; } /* in microseconds */
  70     off_t usecs() const { return _usecs; } /* in microseconds */
  71     off_t msecs() const { return _usecs/1000; } /* in milliseconds */
  72     float secs() const { return _usecs/1000000.0; } /* in seconds */
  73 
  74     //! Time from last mark to last stop (initally zero)
  75     off_t usecs_since_mark() const { return _usecs - _usecs_at_mark; }
  76 };
  77 
  78 #endif
  79